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/**
* benchmark: find a product in product list
* using: for vs forEach vs find
*/
const microtime = require('microtime');
const products = require('../data/products.json');
var selected = [];
products.forEach( pr => {
if (Math.floor(Math.random() * 100) > 85) {
selected.push(pr.id);
}
});
function compare() {
let n = 4;
var f0 = microtime.nowDouble();
for(i=0 ; i < n ; i++) byFor();
var f1 = microtime.nowDouble();
//
var e0 = microtime.nowDouble();
for(i=0 ; i < n ; i++) byEach();
var e1 = microtime.nowDouble();
//
var b0 = microtime.nowDouble();
for(i=0 ; i < n ; i++) byFind();
var b1 = microtime.nowDouble();
return {
n: n,
for: f1-f0,
items_for: byFor(),
each: e1-e0,
items_each: byEach(),
find: b1-b0,
items_find: byFind(),
sel: selected,
}
}
function byFor() {
var items = [];
var notFound = [];
var found;
selected.forEach( id => {
found = false;
for(i = 0; i < products.length; i++) {
if (products[i].id == id) {
items.push(products[i]);
found = true;
break;
}
}
if (!found) notFound.push(id)
})
return {items: items, nf: notFound};
}
function byEach() {
var items = [];
var notFound = [];
var found;
selected.forEach( id => {
found = false;
products.forEach( pr => {
if (pr.id == id) {
items.push(pr);
found = true;
}
});
if (!found) notFound.push(id)
});
return {items: items, nf: notFound};
}
function byFind() {
var items = [];
var notFound = [];
var result;
selected.forEach( id => {
found = false;
result = products.find((pr) => pr.id == id);
if (result === undefined) notFound.push(id)
else items.push(result);
});
return {items: items, nf: notFound};
}
module.exports = {
compare,
byFor
}
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